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61.
Nikolaas Tinbergen provided an elegantly comprehensive guide to behavioral research with his Four Questions. Unsurprisingly,
these questions summarize the different aspects that are vital to an evolutionary perspective. In this article, the authors
describe how they use these Four Questions (plus one they have added regarding the role of culture) to facilitate evolution
education in the human-oriented disciplines. The use of evolutionary theory in these fields is young, and educating new members
of these fields in evolutionary theory is an even newer idea. Tinbergen’s Four Questions (Plus One) make the goals of an evolutionary
perspective clear and the application of the mechanisms of evolution apparent. It can effectively dispel myths that surround
evolutionary theory, like genetic determinism and hyperadaptationism, and can help ameliorate other ideological concerns.
Finally, it is suggested that it is a heuristic that encourages students to make the transition from understanding the mechanisms
of evolution in biology to applying this knowledge in cross-disciplinary research. 相似文献
62.
Timm Konold A Robin Sayers Amanda Sach Gemma E Bone Steven van Winden Gerald AH Wells Marion M Simmons Michael J Stack Angus Wear Steve AC Hawkins 《BMC veterinary research》2010,6(1):53
Background
Various clinical protocols have been developed to aid in the clinical diagnosis of classical bovine spongiform encephalopathy (BSE), which is confirmed by postmortem examinations based on vacuolation and accumulation of disease-associated prion protein (PrPd) in the brain. The present study investigated the occurrence and progression of sixty selected clinical signs and behaviour combinations in 513 experimentally exposed cattle subsequently categorised postmortem as confirmed or unconfirmed BSE cases. Appropriate undosed or saline inoculated controls were examined similarly and the data analysed to explore the possible occurrence of BSE-specific clinical expression in animals unconfirmed by postmortem examinations. 相似文献63.
Shivani M Chidrawar Naeem Khan Y L Tracey Chan Laxman Nayak Paul AH Moss 《Immunity & ageing : I & A》2006,3(1):10-8
Background
Natural killer (NK) cells are cytotoxic lymphocytes that lack CD3 and express variable levels of CD16, CD56 and CD57. In recent years NK cells have been categorised into two major groups based on the level of CD56 expression. This phenotypic classification correlates with functional activity as CD56bright NK cells are the major cytokine producing subset whereas CD56dim NK cells exhibit greater cytotoxic activity. Previous studies have revealed a reduction in total NK cell numbers in association with ageing and this study sought to determine the potential influence of ageing on the number of NK cell subsets within peripheral blood. 相似文献64.
Everett D. Hendricks Ben D. Massey Earl F. Nation Charles A. Gallup Ben D. Massey Jr. 《The Western journal of medicine》1969,111(2):84-86
Results in 96 patients who had total retropubic prostatectomy were reviewed. The most common complications were impotence and difficulty with urinary control. The most serious were rectal injury and vesical neck contracture. Twenty-eight of 33 patients who were followed for five years after operation and eight of twelve who were followed for ten years were alive without evidence of recurrence of cancer. Evidence of recurrence was found only in patients in whom cancer had spread beyond the parenchyma of the prostate before operation. There were no operative deaths. 相似文献
65.
Eman A.E. Badr Abd El-Aleem Hassan Abd El-Aleem Samah EL-Ghlban Asmaa AH. Swelm Mahmoud Emara 《Biochemistry and Biophysics Reports》2019
ObjectivesThe prognosis of high-risk patients might be greatly ameliorated using genetic predisposition risk factors. Sympathetic activity and innate immunity related to neuropeptide Y function may be related to dyslipidemia and atherosclerosis. The aim of this study is to detect the correlation between Neuropeptide Y (NPY) SNP rs16147 and its gene expression in chronic kidney disease with and without hypertension.MethodsThis study carried out on 150 subjects who were divided into 3 main groups group (I) 50 CKD patients with hypertension, group (II) 50 CKD patients without hypertension and group (III) 50 healthy individuals. Carotid intima media thickness (CIMT) was measured by Ultrasound. Kidney function test and lipid profile were performed. Genotyping and gene expression of neuropeptide Y (NPY) were performed using real time PCR.ResultsThere was a significant increase in number and percentage of CC genotype and C allele of NPY SNP distribution in CKD patients with and without hypertension when compared to controls. A significant association was found between CC genotype and C allele and the risk of CKD with hypertension with odd ratio 3.26 and 1.77, respectively. There is a significant positive correlation between NPY gene expression level and CIMT among chronic kidney disease patients with highest level of TC, LDLc and CIMT among CC genotype of NPY gene.ConclusionA significant association was found between CC genotype and C allele of NPY at rs16147 with increase NPY gene expression and risk of developing hypertension in CKD. 相似文献
66.
Alejandro Larios Mora Laurent Detalle Albert Van Geelen Michael S. Davis Thomas Stohr Jack M. Gallup Mark R. Ackermann 《PloS one》2015,10(12)
Rationale
Respiratory syncytial virus (RSV) infection in preterm and newborn infants can result in severe bronchiolitis and hospitalization. The lamb lung has several key features conducive to modeling RSV infection in human infants, including susceptibility to human strains of RSV such as the A2, Long, and Memphis Strain 37 (M37). In this study, the kinetics of M37 infection was investigated in newborn lambs in order to better define clinical, viral, physiological, and immunological parameters as well as the pathology and lesions.Methods
Newborn lambs were nebulized with M37 hRSV (6 mL of 1.27 x 107 FFU/mL), monitored daily for clinical responses, and respiratory tissues were collected from groups of lambs at days 1, 3, 4, 6, and 8 post-inoculation for the assessment of viral replication parameters, lesions and also cellular, immunologic and inflammatory responses.Results
Lambs had increased expiratory effort (forced expiration) at days 4, 6, and 8 post-inoculation. Nasal wash lacked RSV titers at day 1, but titers were present at low levels at days 3 (peak), 4, and 8. Viral titers in bronchoalveolar lavage fluid (BALF) reached a plateau at day 3 (4.6 Log10 FFU/mL), which was maintained until day 6 (4.83 Log10 FFU/mL), and were markedly reduced or absent at day 8. Viral RNA levels (detected by RT-qPCR) in BALF were indistinguishable at days 3 (6.22 ± 0.08 Log10 M37 RNA copies/mL; mean ± se) and 4 (6.20 ± 0.16 Log10 M37 RNA copies/mL; mean ± se) and increased slightly on day 6 (7.15 ± 0.2 Log10 M37 RNA copies/mL; mean ± se). Viral antigen in lung tissue as detected by immunohistochemistry was not seen at day 1, was present at days 3 and 4 before reaching a peak by day 6, and was markedly reduced by day 8. Viral antigen was mainly present in airways (bronchi, bronchioles) at day 3 and was increasingly present in alveolar cells at days 4 and 6, with reduction at day 8. Histopathologic lesions such as bronchitis/bronchiolitis, epithelial necrosis and hyperplasia, peribronchial lymphocyte infiltration, and syncytial cells, were consistent with those described previously for lambs and infants.Conclusion
This work demonstrates that M37 hRSV replication in the lower airways of newborn lambs is robust with peak replication on day 3 and sustained until day 6. These findings, along with the similarities of lamb lung to those of infants in terms of alveolar development, airway branching and epithelium, susceptibility to human RSV strains, lesion characteristics (bronchiolitis), lung size, clinical parameters, and immunity, further establish the neonatal lamb as a model with key features that mimic RSV infection in infants. 相似文献67.
Defining a minimal cell: essentiality of small ORFs and ncRNAs in a genome-reduced bacterium 下载免费PDF全文
Verónica Lloréns‐Rico Francis J O'Reilly Judith AH Wodke E Besray Unal Eva Yus Sira Martínez Robert J Nichols Tony Ferrar Ana Vivancos Arne Schmeisky Jörg Stülke Vera van Noort Anne‐Claude Gavin Peer Bork Luis Serrano 《Molecular systems biology》2015,11(1)
Identifying all essential genomic components is critical for the assembly of minimal artificial life. In the genome-reduced bacterium Mycoplasma pneumoniae, we found that small ORFs (smORFs; < 100 residues), accounting for 10% of all ORFs, are the most frequently essential genomic components (53%), followed by conventional ORFs (49%). Essentiality of smORFs may be explained by their function as members of protein and/or DNA/RNA complexes. In larger proteins, essentiality applied to individual domains and not entire proteins, a notion we could confirm by expression of truncated domains. The fraction of essential non-coding RNAs (ncRNAs) non-overlapping with essential genes is 5% higher than of non-transcribed regions (0.9%), pointing to the important functions of the former. We found that the minimal essential genome is comprised of 33% (269,410 bp) of the M. pneumoniae genome. Our data highlight an unexpected hidden layer of smORFs with essential functions, as well as non-coding regions, thus changing the focus when aiming to define the minimal essential genome. 相似文献
68.
Cell-mass production of Serratia marcescens was studied in dialysis systems in which growth was managed in a fermentor remote from, but connected by conduits and pumps with, a nutrient reservoir. Dialysis was accomplished with membrane tubing in either the fermentor or the reservoir, or best with membrane sheet in a plate-and-frame dialyzer that was remote from but connected with both vessels. Growth trials with these systems demonstrated their ability to produce virtually unlimited population density in a liquid culture, viable counts in excess of 10 cells/ml and partial cell volume of 50% being attained. The system used for growth also may be used, after the growth cycle, to concentrate cells still further by osmotic dehydration with a hydrophilic colloid. The dialyzer-dialysis system that was evolved permits independent control of the component operations and is believed to be adaptable to any desired scale of size. 相似文献
69.
Martijn AH Oude Voshaar Peter M ten Klooster Erik Taal Eswar Krishnan Mart AFJ van de Laar 《Arthritis research & therapy》2012,14(2):R47-7
Introduction
Patient-reported physical function is an established outcome domain in clinical studies in rheumatology. To overcome the limitations of the current generation of questionnaires, the Patient-Reported Outcomes Measurement Information System (PROMIS®) project in the USA has developed calibrated item banks for measuring several domains of health status in people with a wide range of chronic diseases. The aim of this study was to translate and cross-culturally adapt the PROMIS physical function item bank to the Dutch language and to pretest it in a sample of patients with arthritis.Methods
The items of the PROMIS physical function item bank were translated using rigorous forward-backward protocols and the translated version was subsequently cognitively pretested in a sample of Dutch patients with rheumatoid arthritis.Results
Few issues were encountered in the forward-backward translation. Only 5 of the 124 items to be translated had to be rewritten because of culturally inappropriate content. Subsequent pretesting showed that overall, questions of the Dutch version were understood as they were intended, while only one item required rewriting.Conclusions
Results suggest that the translated version of the PROMIS physical function item bank is semantically and conceptually equivalent to the original. Future work will be directed at creating a Dutch-Flemish final version of the item bank to be used in research with Dutch speaking populations. 相似文献70.
R. Nathan Pipitone Gordon G. Gallup Jr 《Ethology : formerly Zeitschrift fur Tierpsychologie》2012,118(3):281-291
Research shows that hormonal changes in women across the menstrual cycle affect vocal production. Most work has documented shifts at high fertility times (i.e., ovulation) or during premenstruation. However, hormonal changes at menstruation also affect female physiology and behavior and could affect vocal production. The present studies investigated perceptual differences in voices recorded during menstruation compared with recordings taken at other times of the menstrual cycle. Results show that male raters could reliably identify voices recorded during menstruation with or without the presence of a voice recorded closest to ovulation. In addition, voices recorded at menstruation were identified as being the most unattractive. These findings indicate that voice recordings taken at times of lowest fertility may uniquely impact women’s vocal production and that perceptions of voice based on cycle phase are not specific to the time of heightened fertility. Implications for the evolution of human menstrual cycle cues are discussed. 相似文献